Embodiments of the present application relate generally to temperature control in an x-ray imaging system. Particularly, certain embodiments relate to controlling temperatures in both the x-ray source and in the x-ray detector in a mobile x-ray imaging system.
X-ray imaging systems may include temperature-sensitive components, such as an x-ray source and an x-ray detector. Temperature-sensitive components may perform more efficiently when the temperatures of the components are controlled. An x-ray source, for example, may heat up during operation. An x-ray tube may only convert a fraction of energy into x-rays. For example, an x-ray tube may only convert 1% of input energy into x-rays, and the remaining 99% of energy may be converted into heat. For example, if an x-ray tube draws 450 W of power, the tube may generate 446 W of thermal energy.
At a certain temperature, the x-ray tube may lose efficiency, or the generated heat may be relatively difficult to contain given that the system may be intended for use in proximity to human beings. For example, an x-ray tube may incorporate a fluid (e.g. oil) in a housing (e.g. aluminum housing). If the fluid temperature rises to or above a certain temperature (e.g. 90 C), the fluid may become overly expansive. For example, the fluid may expand and destroy a housing, such as an aluminum housing, over a certain temperature. Therefore, it may be desirable to prevent the x-ray source from exceeding a maximum recommended operating temperature. Additional cooling systems may be required to prevent overheating of an x-ray tube, while still allowing system operation.
X-ray detectors, such as solid-state x-ray detectors, may also require temperature control for efficient operation. For example, solid-state x-ray detectors may contain relatively sensitive components. The performance of some solid-state components may be most efficient within a given temperature range. If temperatures exceed a recommended range, the performance of the components may deteriorate. For example, the signal-to-noise ratio of certain sensitive components may decrease when the temperature exceeds a preferred operating range. Furthermore, the detector may be calibrated for efficient performance around a particular temperature (e.g. 30 C). If the detector temperature strays to far from the calibration temperature (e.g. +/−5 C from the calibration temperature), the performance of the detector may become noticeably less efficient. Consequently, it may be desirable to maintain an x-ray detector, such as a solid-state x-ray detector, within a recommended temperature range.
Using fans to dissipate heat in an x-ray source and/or x-ray detector may introduce undesirable effects. For example, air cooling an x-ray source may require a relatively large airflow across the x-ray source. A fan capable of creating such an airflow may also cause undesirable turbulence and airflow in a clinical environment.
Instead, liquid-based temperature control systems may provide certain advantages, especially as applied to x-ray imaging systems in clinical environments. For example, liquid-based temperature control systems may not generate undesired airflow in a substantially sterile environment. Additionally, it may be possible to design liquid-based systems without a pump or other moving part close to a patient. Furthermore liquid-based systems may provide relatively good subcooling capacity for a given volume ratio. Nonetheless, liquid-based temperature control systems may be more expensive than air-based systems. Thus, providing a separate temperature control system for each temperature sensitive component (e.g. a separate system for both the x-ray source and the x-ray detector) may add substantial cost to an x-ray imaging system.
Thus, there is a need for methods and systems that control temperatures in a plurality of temperature-sensitive components in an x-ray imaging system. Additionally, there is a need for methods and systems that control temperatures in an x-ray imaging system without needless additional costs. There is a need for temperature control methods and systems that improve operations for x-ray imaging systems as perceived by both the clinician and the patient.